Oh...you're gonna get lots of varying opinions on this one. I belong to the "landscaping fabric" group, but many have great success with newspaper/cardboard. The weeds I was dealing with before building my box were VERY invasive, and the fabric controls them very well. The fabric was simply laid on top of the weeds/grass and no digging was necessary.

I'm hoping someone dealing with Bermuda grass will answer. I too am in the landscape fabric club, but I don't have to deal with grass that will tear through it. From what I understand, Bermuda grass is tough, nasty stuff. Maybe fabric, or cardboard would work to smother them. I don't know. Sorry

Bermuda Grass is a royal PITA. The runners will go through landscape fabric and grow a mile, if they have to, just to invade your garden. I'd go with digging it out, cardboard, AND landscape fabric. Even so, it will probably find its way into your garden somehow.

I used to own a design-construction business in CA, and by FAR the worst problem I had was bermuda suppression. I had one client - no exaggeration, on a slab pull up their bedroom carpet and bermuda runners were underneath the pad.

So. IME you'd better not just lay something down and hope it works, as one tiny feeder root can become a runner, then you are done for. You need to spray Roundup, wait, see what grows back, spray that, wait, spray. 3x will likely do it. Dig up a square down 8 inches, screen out the roots, as there is a good chance there are dormant roots in there. Then kill the bermuda at least 5' from your bed, or dig down 2 feet and triple some landscape fabric.

Again, do NOT lay something down, build your bed, fill with dirt. Don't do it. But as sb said, it'll find its way back in. The devil's weed. We studied in in two classes at UCD and as much as I hated it, it is an amazing, amazing plant. Do not underestimate it. Sorry to be a downer. I had it in my yard in Sacto and pulling it out of beds was my biggest chore by far. You must be on top of it.

Could someone please (note drawn out teenager's whine) have posted this before I laid my beds last fall using only weed block? :) *sigh* oh well. We'll see how it goes. It wasn't a problem last year, but I suppose it had already gone dormant during the fall. Any suggestion for how to deal with it now? The beds are 12 inches deep.

Sorry Ribbit. I used Roundup while the Bermuda grass was still green, then watched for any green patches to pop back up so I could hit them again. Then I used thick layers of newspaper in the bottoms of my boxes and kept my fingers crossed. I'll probably find out this year if it was successful. My 3' x 22' bed along the fence line got Roundup, then I dug out the roots the best I could. That bed is not raised and filled like the others, so no weed barrier was used. I didn't have any more Bermuda grass show up that entire season, but I'm still holding my breath.

Solarize it, Sanbpate. I've tried everything to get rid of bermuda ~ Roundup (ex did it, not me ~ don't like the stuff), tried to dig it out, built a 12" tall raised bed on top of it. Nothing worked except solarizing. Oh ~ and a slightly overstocked chicken tractor. That worked great, too.

Ribbit, you might try solarizing still, but you may have to do what I did when I built the bed over it ~ after two or three years of fighting it, I dismantled the bed (there still were runners at the original ground level! ARRRGH!) and solarize.

Both of you, be sure to follow the directions to the letter. Make sure it's wet underneath and the edges are tucked very well.

we don't have bermuda grass but my bed is near a blackberry bush that thinks it owns my lot and the runners come up everywhere. I laid down cardboard from a frig box then I wet newspaper and laid it really thick in one direction then another and criss crossed several layers, added some stone on the edges to keep it down. seems to be working.